U.S. patent application number 15/313334 was filed with the patent office on 2017-07-06 for optical stimulation device and method for programming.
This patent application is currently assigned to LEIBNIZ-INSTITUT FUER NEUROBIOLOGIE MAGDEBURG. The applicant listed for this patent is LEIBNIZ-INSTITUT FUER NEUROBIOLOGIE MAGDEBURG, OTTO-VON-GUERICKE-UNIVERSITAET MAGDEBURG, OTTO-VON-GUERICKE-UNIVERSITAET MEDIZINISCHE FAKULTAET. Invention is credited to Hans-Joachim HEINZE, Kathrin JANITZKI, Michael LIPPERT, Frank OHL.
Application Number | 20170189712 15/313334 |
Document ID | / |
Family ID | 53276101 |
Filed Date | 2017-07-06 |
United States Patent
Application |
20170189712 |
Kind Code |
A1 |
LIPPERT; Michael ; et
al. |
July 6, 2017 |
OPTICAL STIMULATION DEVICE AND METHOD FOR PROGRAMMING
Abstract
The invention relates to an optical stimulation device for
stimulating nerve cells, wherein the stimulation device has at
least one implant component, which is designed for implanting in a
natural inner cavity of the body of a living being, through which
cavity a bodily fluid flows, having the following features: a) the
implant component has at least one supporting structure, which can
be expanded in a radial direction for fastening in the natural
inner cavity. b) a plurality of light sources is fastened to the
supporting structure, which light sources are designed to emit
light in the radial direction with respect to the supporting
structure, c) a plurality or electrodes is fastened to the
supporting structure, which electrodes are designed to capture
electrical body signals, d) the supporting structure has a
plurality of openings and/or channels, through which the bodily
fluid can flow after implantation in the body. The invention
further relates to a method for programming the parameter memory of
a stimulation device.
Inventors: |
LIPPERT; Michael; (Leipzig,
DE) ; OHL; Frank; (Osterweddingen, DE) ;
JANITZKI; Kathrin; (Magdeburg, DE) ; HEINZE;
Hans-Joachim; (Magdeburg, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LEIBNIZ-INSTITUT FUER NEUROBIOLOGIE MAGDEBURG
OTTO-VON-GUERICKE-UNIVERSITAET MAGDEBURG
OTTO-VON-GUERICKE-UNIVERSITAET MEDIZINISCHE FAKULTAET |
Magdeburg
Magdeburg
Magdeburg |
|
DE
DE
DE |
|
|
Assignee: |
LEIBNIZ-INSTITUT FUER NEUROBIOLOGIE
MAGDEBURG
Magdeburg
DE
|
Family ID: |
53276101 |
Appl. No.: |
15/313334 |
Filed: |
May 22, 2015 |
PCT Filed: |
May 22, 2015 |
PCT NO: |
PCT/EP2015/061400 |
371 Date: |
November 22, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61N 2005/0629 20130101;
A61B 2018/00839 20130101; A61N 2005/0612 20130101; A61N 2005/0626
20130101; A61N 2005/067 20130101; A61N 2005/0652 20130101; A61N
5/0622 20130101; A61N 5/0601 20130101; A61N 2005/0651 20130101 |
International
Class: |
A61N 5/06 20060101
A61N005/06 |
Foreign Application Data
Date |
Code |
Application Number |
May 23, 2014 |
DE |
102014107298.7 |
Claims
1. An optical stimulation device for stimulating nerve cells, the
stimulation device having at least one implant component configured
for implantation in a natural inner cavity of the body of a living
organism, through which cavity a body fluid flows, having the
following features: a) the at least one implant component has at
least one support structure which is expandable in a radial
direction for fixation in the natural inner cavity, b) attached to
the support structure is a multiplicity of light sources which are
configured for radiation of light in the radial direction with
respect to the at least one support structure, c) attached to the
at least one support structure is a multiplicity of electrodes
which are configured for capturing electric body signals, d) the at
least one support structure has multiple openings and/or channels
through which the body fluid can flow after implantation in the
body.
2. The stimulation device as claimed in claim 1, wherein the
implant component has a control electronics system ) and/or is
connected via lines to a control electronics system arranged
distantly from the implant component, wherein the control
electronics system is configured for signal conditioning and/or
signal processing of signals received via the electrodes and/or for
activating the light sources.
3. The stimulation device as claimed in claim 2 wherein the control
electronics system has a parameter memory in which an item of
information is stored for each light source, regarding whether the
light source is activatable or not for the purposes of
stimulation.
4. The stimulation device as claimed in claim 3 wherein the light
sources are attached to the support structure in a predefined
position with respect to the electrodes.
5. The stimulation device as claimed in claim 1 wherein the support
structure has, in a nonexpanded state, a circumference of less than
10 mm.
6. The stimulation device as claimed in claim 1 wherein the support
structure comprises a material having a high thermal
conductivity.
7. The stimulation device as claimed in claim 1 wherein one or more
light sources have thermally conductive heat sinks.
8. The stimulation device as claimed claim 1 wherein in the implant
component has a coupling element via which the implant component is
coupleable to a flexible guide rod to be coupled to the implant
component for carrying out the implantation process, the coupling
of the coupling element to the flexible guide rod being
disengageable by actuation of a release mechanism.
9. The stimulation device as claimed in claim 1 wherein at least
some or all light sources are individually activatable.
10. The stimulation device as claimed claim 1 wherein the light
sources and/or the electrodes are attached on a flexible support
material which is attached to the support structure.
11. A method for programming the parameter memory of a stimulation
device as claimed in claim 3, wherein all light sources for light
emission are actuated first, signals subsequently captured by means
of the electrodes are evaluated or signals captured by other
nerve-signal capture methods are evaluated, one or more individual
light sources from the total multiplicity of light sources present
that will be activatable in future are determined therefrom, and an
identification of "activatable" is stored in the parameter memory
for these one or more individual light sources and the
identification "nonactivatable" is stored for all other light
sources of the multiplicity of light sources.
12. The simulation device as claimed in claim 5 wherein the
circumference is less than 6 mm.
13. The simulation device as claimed in claim 6 wherein the thermal
conductivity is greater than 10 W/mK.
14. The simulation device as claimed in claim 7 wherein multiple
light sources have thermally conductive heat sinks.
Description
[0001] The invention relates to an optical stimulation device for
stimulating nerve cells as claimed in claim 1. The invention also
relates to a method for programming the parameter memory of a
stimulation device as claimed in claim 10.
[0002] In general, the invention relates to the field of optical
stimulation of nerve cells, i.e., of stimulation by light. The
invention thus relates to the field of optogenetics. The
development of optogenetics, of the sensitization of normal nerve
cells to light by genetic techniques, nurtures the hope of being
able to use light to treat a range of diseases by temporally and
spatially selective activation or inhibition of neuronal
structures. Current systems are based on the stereotactic placement
of electrodes and light sources directly in brain tissue or on the
surface of the brain. This is associated with complicated surgical
procedures and corresponding risks. Furthermore, the necessary
stereotactic planning complicates broad applicability.
[0003] Moreover, the implantation of the light-generating
structures leads to a not negligible heat input in the brain. To
avoid brain damage, the possible attainable output density of the
light signals is greatly limited.
[0004] It is therefore an object of the invention to specify an
optical stimulation device for stimulating nerve cells, which
device has a higher efficiency together with simplified
applicability and thereby opens the way to a broader applicability
of optogenetic treatment methods.
[0005] This object is achieved as claimed in claim 1 by an optical
stimulation device for stimulating nerve cells, the stimulation
device having at least one implant component configured for
implantation in a natural inner cavity of the body of a living
organism, through which cavity a body fluid flows, having the
following features:
[0006] a) the implant component has at least one support structure
which is expandable in the radial direction for fixation in the
natural inner cavity,
[0007] b) attached to the support structure is a multiplicity of
light sources which are configured for radiation of light in the
radial direction with respect to the support structure,
[0008] c) attached to the support structure is a multiplicity of
electrodes which are configured for capturing electric body
signals,
[0009] d) the support structure has multiple openings and/or
channels through which the body fluid can flow after implantation
in the body.
[0010] The invention has the advantage that, for the first time, it
is possible to specify an optical stimulation device for
stimulating nerve cells, more particularly nerve cells of the
brain, which can be deployed by noninvasive or minimally invasive
surgical techniques. More particularly, the implant component can
be placed endoscopically in the desired inner cavity of the body
and anchored there by effecting a fixation in the natural inner
cavity by expansion of the support structure in the radial
direction. The fixation can, for example, be effected by balloon
expansion, as known from stents. To fit and place the implant
component in the inner cavity, it is, for example, possible to use
a flexible guide rod, for example in the form of a catheter.
Advantageously, it is, for example, possible to use a ventricle
space for the placement of the implant component. In this case, the
insertion of the implant component into the ventricle space is
performable in a noninvasive manner, by the wall of the ventricle
not being broken through, but by the placement of the implant
component taking place via the openings of the ventricle system. A
minimally invasive placement is possible too when there is a
piercing of a brain structure which leads to fewest possible
adverse effects. Moreover, the minimally invasive or noninvasive
nature of the stimulation device according to the invention allows
its exchange in the event of a defect or a further development of
the stimulation device. A repositioning is possible too without
additional damage occurring in the brain tissue.
[0011] The open structure of the support structure, i.e., the
openings and/or channels, allows a flow through the support
structure and thus the implant component after implantation in the
body by means of body fluid, making it possible for a cooling of
the light sources to take place in a natural manner. In this way,
it is possible to resolve the heat problem due to the light sources
that was mentioned at the beginning. In the case of placement of
the implant component in the ventricle space, as mentioned, the
cerebrospinal fluid can be directly used to cool the light sources.
As a result, an especially efficient cooling is possible, enabling
considerably higher radiatable light outputs. At the same time,
brain tissue damage due to unallowable heating can be avoided.
[0012] Owing to the radiation of light in the radial direction with
respect to the support structure, the light is directly emitted
into the surrounding tissue. In this connection, the radiation of
light need not exclusively take place exactly in the radial
direction. To achieve a high optical efficiency, it is advantageous
when the radial component of the direction of light radiation is
the predominant component.
[0013] By means of the optical stimulation device according to the
invention, a treatment of the following diseases is possible:
[0014] Stimulation of the locus coeruleus:
[0015] Neurodegenerative diseases such as Parkinson's disease and
Alzheimer's disease, which are characterized by an early
degeneration of the LC,
[0016] Severe psychiatric symptoms, such as major depression,
Korsakoff's syndrome, anxiety disorders, PTSD, which are
characterized by altered discharges of the LC,
[0017] Disorders of wakefulness/locked-in syndrome through
stimulation of the locus coeruleus or of the ARAS,
[0018] In the case of narcolepsy or after unilateral cerebral
infarction or bleeding in the brainstem region,
[0019] Disorders of autonomous control loops through
stimulation/inhibition of the hypothalamus,
[0020] Eating disorders, hyperactivation of the HPA axis in the
course of many diseases, therapy-resistant hypertonia,
[0021] Addictions and psychoses through indirect stimulation of
frontal cortex areas via activation of ascending monoaminergic
pathways (e.g., of the medial forebrain bundle, which stretches
from the VTA and the LC to the nucleus accumbens),
[0022] Neurodegenerative diseases/memory disorders through an
influence on the hippocampus (placement of the implant component in
the inferior horn of the lateral ventricle)
[0023] Even in the absence of a genetic influence, it is possible
to advantageously use the optical stimulation device according to
the invention. This is possible owing to the presence of endogenous
light-sensitive nerve cells in the brain of vertebrates. In
addition, it is possible to utilize thermal effects of infrared
light for the focal heating of certain brain structures in order to
modulate the activity thereof. Likewise possible is a utilization
of the suppression of neuronal activity by means of the bleaching
properties of blue and green light on the flavoproteins of the
respiratory chain.
[0024] By means of a direct light stimulation without added
optogenetic proteins, a treatment of therapy-resistant severe
depressions, for example, appears possible.
[0025] According to an advantageous development of the invention,
the implant component has a control electronics system or is
connected via lines to a control electronics system arranged
distantly from the implant component, the control electronics
system being configured for signal conditioning and/or signal
processing of the signals received via the electrodes and/or for
activating the light sources. The control electronics system can be
designed as one piece or as multiple pieces, for example in the
form of a headstage electronics system directly arranged on or at
the implant component and of a distantly arranged main electronics
system which is connected via lines to the implant component and
especially the headstage electronics system thereof. In this way,
the necessary electronics system can, as far as necessary, be
directly arranged at the implant component, for example in order to
allow an immediate signal conditioning of the signals of the
electrodes. As a result, the headstage electronics system can be
kept small in terms of structure. Further necessary components can
then be accommodated in the main electronics system.
[0026] The light sources can be electric light sources, for example
in the form of semiconductor light sources, especially in the form
of light-emitting diodes (LED) or laser diodes. The light sources
can also be passive light sources, for example in the form of
light-emitting surfaces of optical waveguides or prisms arranged at
optical waveguides, micromirrors or other optics. In the case of
passive light sources, the lines leading to the light sources can
be especially optical waveguides, for example in the form of glass
fibers. This has the advantage that the optical stimulation device
is MRI-compatible, i.e., does not interfere with the recordings by
means of a magnetic resonance (MRI) scanner. If the light sources
used are electric light sources arranged at or in the implant
component, the lines used are electric conductors (cables). The
light sources attached to the support structure can also be a
combination of electric light sources and passive light
sources.
[0027] According to an advantageous development of the invention,
the light sources are attached to the support structure in a
predefined position with respect to the electrodes.
[0028] According to an advantageous development of the invention,
the control electronics system has a parameter memory in which an
item of information is stored for each light source, regarding
whether the light source is activatable or not for the purposes of
stimulation. This has the advantage that the placement of the
implant component in the inner cavity of the body is simplified,
since an especially high precision of positioning is not required.
Instead, the implant component can be "overloaded", so to speak,
with the light sources, i.e., can have more light sources than is
necessary for the actual nerve stimulation. Owing to the known
position of the light sources with respect to the electrodes at the
support structure, it is possible, by means of trial-based
activation of individual light sources and receiving of the
electrode signals, to test which light sources are most favorably
oriented with respect to the nerve cells. For said light sources,
it is then possible to store in the parameter memory the item of
information that the light source is activatable for the purposes
of stimulation. For the remaining light sources, it is possible to
store the item of information that it is not activatable for the
purposes of stimulation and accordingly remains switched off in
later operation of the optical stimulation device. As a result, the
electric activation and thus the associated heat input are limited
to what is necessary. There is no unnecessary activation of light
sources which have no influence or no substantial influence on the
nerve cells.
[0029] The identification of the activatable light sources can be
carried out by measurement via the electrodes themselves or by
means of a response measured in another way, for example by EEG,
behavioral response, functional magnetic resonance imaging, PET,
SPECT, pharmacological methods. If the identification of the
activatable light sources is not carried out by measurement via the
electrodes, it is not absolutely necessary to arrange the light
sources at the support structure in a predefined position with
respect to the electrodes.
[0030] According to an advantageous development of the invention,
the support structure has, in the nonexpanded state, a
circumference of less than 10 mm, more particularly less than 6 mm.
This has the advantage that a minimally invasive or noninvasive
placement of the implant component is possible in virtually any
body of a living organism.
[0031] According to an advantageous development of the invention,
the support structure comprises a material having a high thermal
conductivity. More particularly, the thermal conductivity is
greater than 10 W/mK. This has the advantage that the support
structure additionally contributes to cooling by better transfer of
the heat arising at the light sources to the body fluid which
serves as coolant and which is situated in the inner cavity
together with the implant component.
[0032] According to an advantageous development of the invention,
one, multiple or all light sources have thermally conductive heat
sinks. As a result, the dissipation of heat from the light sources
is further improved.
[0033] According to an advantageous development of the invention,
the implant component has a coupling element via which the implant
component is coupleable to a flexible guide rod to be coupled to
the implant component for carrying out the implantation process,
the coupling of the coupling element to the flexible guide rod
being disengageable by actuation of a release mechanism. This is
additionally beneficial for a minimally invasive or noninvasive
placement of the implant component in the inner cavity of the body.
The flexible guide rod can, for example, be designed as an
endoscope or a catheter. By means of the release mechanism, which
can, for example, be remotely operable from a handle of the
flexible guide rod, it is possible, after correct placement of the
implant component in the inner cavity of the body, to disengage the
guide rod therefrom and to remove it from the body. Beforehand, it
is possible, via an expansion mechanism which is likewise
triggerable via the flexible guide rod, to expand the support
structure in order to fix the implant component in the inner cavity
of the body.
[0034] According to an advantageous development of the invention,
some or all light sources are individually activatable. This has
the advantage that, through targeted activation of certain light
sources, it is possible to realize special treatment methods which
would not be possible in the case of simultaneous activation of all
light sources. As a result, the application range of the optical
stimulation device is further improved.
[0035] According to an advantageous development of the invention,
the light sources and/or the electrodes are attached on a flexible
support material which is attached to the support structure. The
flexible support material can, for example, be a silicone tube or a
MEMS structure. In this connection, the flexible support material
is formed with openings and/or channels at least to the extent that
the desired through-flow of the body fluid is ensured. As a result,
the producibility of the optical stimulation device is improved.
For instance, the light sources, for example in the form of
light-emitting diodes or laser diodes, can be printed onto a film
or a silicone material and/or be strung onto the support structure
in a thread-like manner, similar to a string.
[0036] As claimed in claim 10, the invention further provides a
method for programming the parameter memory of a stimulation device
of the abovementioned type, wherein all light sources for light
emission are actuated first of all, the signals subsequently
captured by means of the electrodes are evaluated or signals
captured by other nerve-signal capture methods are evaluated, light
sources from the total of the light sources present that will be
activatable in future are determined therefrom, and the
identification "activatable" is stored in the parameter memory for
these light sources and the identification "nonactivatable" is
stored for all other light sources. Using this method, the precise
placement and adjustment of the implant component in the inner
cavity of the body is simplified, since only an approximate
placement in relation to the stimulatory nerve cells is initially
necessary. By means of the described programming of the parameter
memory, the light sources of the implant component which have a
functional effect on the stimulation of the nerve cells are then
detected. The other light sources are then not required from then
on and can be designated as "nonactivatable". A further fine
mechanical placement of the implant component is then not
required.
[0037] In jurisdictions in which medical procedures are not
excluded from patent protection, the invention further provides a
method for implanting an optical stimulation device in a body of a
human or animal, wherein an implant component of the optical
stimulation device is placed endoscopically in a ventricle space of
the body and fixed therein. Here, it is possible to use in
particular an implant component of an optical stimulation device of
the above-described type. As a result, it is possible to realize
the abovementioned advantages.
[0038] According to an advantageous development of the invention,
the implant component is fixed in the ventricle space by expanding
a support structure of the implant component.
[0039] The following procedure, executed using the example of
target structures close to aqueducts, is proposed for the
endoscopic placement of the catheter: As in the endoscopic stenting
of an aqueduct stenosis, a small trepanation (1.5 to 2 cm in
diameter) is first performed approx. 2 to 4 cm anterior to the
coronal suture and 2 cm right of the midline. Thereafter, the
anterior horn of the right lateral ventricle is reached via a rigid
or flexible neuroendoscope and, lastly, a French Fogarty balloon
catheter is introduced into the aqueduct via the interventricular
foramen and the third ventricle. The exact placement of the
light-emitting tip of the catheter, in relation to the target
structure, is done in accordance with a distance to a fixed point
in the aqueduct that was previously precisely determined
tomographically. The catheter is fixed via the expansion of the
balloon in the aqueduct. It is thus possible to reach target
structures in the vicinity of the fourth ventricle, especially the
locus coeruleus. Navigation can be trained beforehand by means of
software.
[0040] Another possible path to the fourth ventricle is from the
occipital side via the natural openings to the subarachnoid space.
The fourth ventricle is connected to the cisterna magna via the
median aperture and on both sides to the cisterna pontis via the
lateral aperture. Positioning and anchoring are done similarly to
the above-described manner.
[0041] The invention will be more particularly elucidated below on
the basis of exemplary embodiments with use of drawings.
[0042] FIG. 1 shows an example of a general system structure of the
optical stimulation device. What can be seen is a support structure
2 which is designed as a stent or catheter for example and to which
light sources 3 and surface electrodes 4 are attached. As a result,
an implant component 1 is provided. The implant component 1 has a
headstage electronics system 5 which is directly connected thereto
and which performs a signal conditioning and processing for ingoing
and outgoing signals, for example impedance conversion,
amplification, digitization, activation of the light sources. Here,
light sources 3, for example in the form of LEDs, can be directly
arranged on the support structure 2, or in the form of laser diodes
in the headstage electronics system 5. The light thereof is then
led out via optical waveguides to the positions depicted in the
figure with the light sources 3.
[0043] The headstage electronics system 5 is connected via lines 6
to a main electronics system 7 of the system.
[0044] The main electronics system 7 undertakes data communication
with external instruments 9 through the skin 8 and supplies power
for the operation of the light sources and of the headstage
electronics system 5. The main electronics system 7 can likewise
carry out the interpretation of the signals and a possible feedback
to the light sources and also store and evaluate data internally.
If laser diodes are used, they can also be arranged in the main
electronics system and be connected via optical waveguides to the
implant component 1.
[0045] The headstage electronics system 5 and the main electronics
system 7 form together a control electronics system of the
stimulation device. This has a parameter memory in which a storage
space, for example in the form of a bit or byte, is provided for
each light source 3. In said storage space, it is possible to
individually store for each light source an item of information
regarding whether the light source is activatable or not for the
purposes of stimulation.
[0046] As can be seen in FIG. 2, the light sources 3 or the laser
diodes thereof can be connected in series, and this has the
advantage that wiring is simpler and fewer lines are required.
[0047] As can be seen in FIG. 3, the light sources 3 or the laser
diodes thereof can also be individually controlled by the headstage
electronics system 5 and/or main electronics system 7. This has the
advantage that stimulation can be limited to a certain region by
only some of the light sources present being activated.
[0048] FIG. 4 shows the system structure when using optical
waveguides. The light source provided is an optical component 13
which is arranged at the end of an optical waveguide 10. The
optical component 13 can, for example, be a micromirror, a prism or
a similar optical component changing the direction of radiation.
The optical component 13 reflects the light at an angle into the
body tissue, which light is provided by a laser emitter 12 through
the optical waveguide 10 and optionally an optics system 11
arranged at the optical waveguide 10 on the input side. For the
activation of the laser emitter 12, a driver electronics system 17
is provided, which can, for example, be part of the main
electronics system 7. Owing to the use of optical waveguides, the
optical stimulation device is improved especially with respect to
MRI compatibility.
[0049] FIG. 5 shows the structure and the anchoring of the optical
stimulation device in the head of a human. The implant component 1
having the light sources 3 and the electrodes 4 is placed in a
ventricle space 21 and the cerebrospinal fluid present therein can
be washed around said implant component to cool the light sources.
The implant component and especially the support structure thereof
are sufficiently permeable to liquids in order not to elicit any
stasis. The implant component is connected via the lines 6 to the
main electronics system 7. The main electronics system 7 can be
implanted beneath the skin at a suitable site of the body,
especially at a site other than in the head. The implantation of
the implant component 1 in the brain 20 can be done in a minimally
invasive manner. The implant component 1 can, for example, be
introduced via a path 22 through healthy tissue at a site at which
adverse effects are barely to be expected. Likewise possible is an
implantation via one of the natural openings of the ventricle
system without damaging the brain 20, i.e., via the path 28
depicted.
[0050] FIG. 6 shows the placement of the implant component 1 in the
head. The implant component 1 is situated in a ventricle space 21
of the brain 20. A connection for the lines 6 is ensured by a
drilled hole 22 in the skull 23 or a natural skull opening to the
outside. The main electronics system 7 is situated beneath the skin
8, not necessarily beneath the skin of the skull 23.
[0051] The main electronics system 7 can communicate transdermally
with external instruments 9.
[0052] FIG. 7 shows, with further details, one embodiment of the
implant component 1. A support structure 2 which is constructed
with a lattice structure and which supports the light sources 3 and
the electrodes 4 is placed in the ventricle space next to the brain
20. The support structure 2 is sufficiently permeable to
cerebrospinal fluid by being formed with openings and/or
channels.
[0053] Situated on and/or in the support structure 2 are organic or
crystalline semiconductor light sources 3 and surface electrodes 4
which are contacted by lines 6. The arrows indicate the radiation
of light by the light sources 3 in the radial direction with
respect to the support structure.
[0054] FIGS. 8 to 10 show possible attachments of the light sources
3 and of the electrodes 4 to the support structure 2. FIG. 8 shows
that the light sources 3 and electrodes 4 are applied on the
surface of a flexible support material 18 which is additionally
sufficiently thermally conductive, for example on a silicone
material, for example in the form of a silicone tube, or on a MEMS
structure. The support structure 2 is situated within the support
material 18. The support structure 2 can, for example, be designed
in the form of a stent, which structure allows an expansion to
anchor the implant components in the inner cavity of the body. The
lines 6 can run inside the support structure 2. Alternatively, the
flexible support material 18 can also be arranged at the inner side
of the support structure 2.
[0055] In FIG. 9, it can be seen that the light sources 3 and the
electrodes 4 and also the lines 6 are incorporated into the
thermally conductive flexible support material 18 in terms of
thin-layer or thick-layer technology.
[0056] FIG. 10 shows that the electrodes 4 and the light sources 3
can be directly attached to the support structure 2 and accordingly
participate in the change in shape (expansion).
[0057] FIG. 11 shows one option for the additional cooling of the
light sources via the cerebrospinal fluid. The light sources 3 can
be equipped with small thermally conductive cooling structures
(heat sink) 19 which deliver the heat which arises to the
cerebrospinal fluid. Here, the material of the support structure 2
can additionally have a supportive effect if it is sufficiently
heat-conductive.
[0058] Advantageously, the support structure 2 can, for example, be
formed from one metallic material, similar to customary stents. As
a result, heat dissipation can be further improved.
[0059] FIG. 12 shows the use of optical fibers (optical waveguides
10) in conjunction with optical elements 13 as light sources. To
achieve MRI compatibility and, in addition, higher optical outputs,
glass fibers can be used as optical waveguides 10. To guide the
light to the surrounding tissue, such optical waveguides 10 are
equipped at the end with optical elements 13 such as micromirrors
or prisms, which bring about a deflection into the radial direction
of light radiation. The light can then be radiated to the outside
through the open support structure 2, i.e., in the radial direction
with respect to the support structure.
[0060] FIG. 13 shows the insertion of the implant component 1 by
means of a flexible guide rod 31, for example an endoscope or a
catheter. The guide rod 31 is mechanically coupled to a coupling
element 30 of the implant component. Via a release mechanism which
can be arranged at the flexible guide rod and/or at the implant
component, this coupling can be undone in order to remove the guide
rod 31 after placement of the implant component 1. This is done
after expansion and corresponding anchoring of the implant
component in the inner cavity, in this case in the ventricle space
21, as depicted in FIG. 14.
[0061] As can be additionally seen from FIG. 14, it is intended
that the implant component be used to stimulate nerve cells 24. To
this end, the implant component 1 is first approximately positioned
within the brain 20 at the correct site by means of the guide rod
31. Thereafter, the support structure 2 is expanded, for example by
means of balloon expansion. As a result, the light sources 3 and
the electrodes 4 are pressed against the wall 25 of the ventricle
space 21 without damaging said wall. The guide rod 31 is removed.
What remains is the line 6 for connecting the implant component 1
to the main electronics system 7. A programming of the parameter
memory of the stimulation device is then carried out such that, for
example, the light source 32 is stored as "activatable" and the
light source 33 as "nonactivatable". The nerve cells 24 can then be
stimulated by the activatable light sources 32. The nonactivatable
light sources 33 lying further away can remain switched off to save
energy. The identification of the activatable light sources can be
achieved by trial-based activation of individual light sources and
by measurement of the response of the nerve cells 24. The
measurement can be carried out via the electrodes 4 themselves or
by means of a response measured in another way, for example by EEG,
behavioral response, functional magnetic resonance imaging, PET,
SPECT, pharmacological methods.
* * * * *